In this article is an interesting factoid about where this deadly, brain destroying amoeba can be found: in water heaters kept below 117F. Improbable? Yes. Impossible? No. I am thinking of not only people trying to save energy, but also vacation cabins where water is heated just enough for showers and such. Given variations in thermostats and their performance, a tank set at 120F could be holding water that is cooler.
http://www.wusa9.com/news/article/163275/28/Brain-Eating-Amoeba-Rare-But-Deadly-How-To-Stay-Safe
http://www.wusa9.com/news/article/163275/28/Brain-Eating-Amoeba-Rare-But-Deadly-How-To-Stay-Safe